I. Field of the Invention
The present invention relates generally to safety devices and more particularly to a safety device for locking the elevational height of a lift and preventing unintended collapse of the lift.
II. Description of the Prior Art
Previously known lifts, such as hydraulic lifts commonly used in service stations, have not been provided with safety devices for locking the lift in a fixed elevational position. Consequently, upon failure of the lift, or its power mechanism, the lift would oftentimes collapse to the ground. Collapse of the lift not only causes severe damage to a vehicle positioned on the lift platform but also creates a great safety hazard in that persons standing under the lift would be seriously injured by the collapse of the lift.
In order to reduce the safety hazard of possible collapse of the lift, several previously known locking devices have been developed to prevent the unintended collapse of the lift. These previously known locking mechanisms, however, suffer several disadvantages unknown to the present invention.
In one type of the previously known locking mechanisms for lifts, the locking mechanism only functions to lock the lift when the lift is in its most elevated position. Thus if the lift is lowered somewhat, for example, to permit easier access to the bottom of the vehicle on the lift, the locking mechanism is non-functional thereby resurrecting the original safety hazard.
Other previously known locking mechanisms for lifts are only capable of locking the lift in predetermined increments of elevational height rather than at any desired height. A locking device capable of locking the lift at any desired height provides increased flexibility and therefore is preferred.
Other previously known locking mechanisms for lifts are unduly complex and expensive to not only manufacture and install but also to operate. Such previously known locking devices in addition require extensive maintenance which accordingly increases the cost of the locking mechanism.